Millennial-Scale Variability of the George VI Ice Shelf, Antarctic Peninsula

BENTLEY, M.J.¹, HODGSON, D.A.², NOON, P.², ROBERTS, S.J.³, SMITH, J.A.¹, SUGDEN, D.E.³, VERLEYEN, E.^4
1Department of Geography, University of Durham, South Rd, Durham, DH1 3LE, UK
²British Antarctic Survey, High Cross, Madingley Rd, Cambridge, CB3 0ET, UK
³Department of Geography, University of Edinburgh, Drummond St, Edinburgh, EH8 9XP, UK
⁴Department of Botany (Protistology & Aquatic Ecology Section), University of Gent, Krijgslaan, 281 - S8 B- 9000, Gent, Belgium

Contact e-mail: m.j.bentley@durham.ac.uk

This project uses a combined geomorphological and biological approach to test the hypothesis that the George VI Ice Shelf has waxed and waned in response to Holocene climatic change. An understanding of long-term variability is needed in order to judge the significance of the recent collapse of several Peninsula ice shelves. Moreover, a record of past behaviour provides a means of testing and constraining glaciological models which are needed to predict the response of Antarctic ice sheets and ice shelves to global warming. We have sampled sediments from two epishelf lakes (Moutonnee Lake and Ablation Lake) on the east coast of Alexander Island where the western margin of the ice shelf grounds onshore. The sediments in these lakes should record major changes during periods of ice shelf loss, in particular a shift from mixed freshwater and marine sedimentation to purely marine sedimentation. Preliminary results from the intensive multi-proxy analysis of the cores will be presented, along with limnological and geomorphological data from the present-day catchments of the lakes.